Toggle operated electric vacuum switch



March 5, 1968 Filed Oct. 20, 1966 M. R. JENSEN TOGGLE OPERATED ELECTRICVACUUM SWITCH G) Ll 2 Sheets-Sheet 1 ID v INVENTOR. MERLIN R. JENSEN WEWATTORNEY March 5, 1968 M. R. JENSEN TOGGLE OPERATED ELECTRIC VACUUMSWITCB 2 Sheets-Sheet 2 Filed Oct. 20, 1966 INVENTOR. MERLIN R. JENSENWQM ATTORNEY United States Patent Ofllice 3,372,353 TOGGLE OPERATEDELECTRIC VACUUM SWITCH Merlin R. Jensen, Minneapolis, Minn, assignor toElectric Machinery Mfg. Company, Minneapolis, Minn, a corporation ofMinnesota Filed Get. 20, 1966, Ser. No. 588,104 4 Claims. (Cl. 335-26)ABSTRACT OF THE DESCLOSURE A vacuum electric switch operated by anelectromagnet by means of toggle mechanism and including resilient meansconcentric with one of the contacts for holding the contact in eitherclosed or open position.

The herein disclosed invention relates to electric switch mechanisms andparticularly to a mechanism adapted to handle heavy currents such asutilized in large electric motors.

An object of the invention resides in providing a mechanism utilizing avacuum switch together with an electrically operated opening and closingdevice.

Another object of the invention resides in utilizing a toggle linkagefor the purpose, whereby suflicient pressure can be procured between thecontactors to pass the desired amount of current with minimum arcing.

A still further object of the invention resides in providing resilientmeans in the form of a spring for urging the contactors apart tonormally leave the switch open.

An object of the invention resides in providing additional resilientmeans in the 'form of a spring between the movable contactor and thetoggle linkage to maintain pressure between the contactors at all timeswhen the switch is closed.

Another object of the invention resides in providing interconnectingmeans between the toggle linkage and the movable contactor and againstwhich both springs react.

A feature of the invention resides in constucting the interconnectingmeans with a cylindrical wall having an end wall extending across thesame at one end and a flange extending outwardly therefrom at its otherend.

Other objects of the invention reside in the novel combination andarrangement of parts and in the details of construction hereinafterillustrated and/or described.

In the drawings:

FIGURE 1 is a side elevational View of the invention.

FIGURE 2 is a fragmentary plan sectional view taken on line 2-2 ofFIGURE 1.

FIGURE 3 is a fragmentary plan sectional view taken on line 33 of FIGURE1.

The invention consists of a vacuum-type switch elongated in formtogether with a supporting structure 30 also elongated in form andconnected to and lying in continuation of said vacuum-type switch. Thisstructure is mounted on a truck 40 and is insulated therefrom. A togglelinkage 50 is carried by the support 30 and is actuated by anelectromagnet 70 which is mounted on said truck.

The truck 40 consists of a base 41 having flanges 42 at the sides of thesame and which extend upwardly from said base to form uprights 43, whichare located at the ends of the truck. The flange-s 42 are connectedtogether at their upper ends by means of shelves 44. Between the flanges42 at the lower end of the same are shafts 45 on which are rotatablymounted truck wheels 46. Mounted on the shelves 44 are insulators 47 and48 which support the vacuum switch 10 and the support 30 as will bepresently described.

3,372,353 Patented Mar. 5, 1968 The switch 10 consists of a tube 11constructed in two sections 11a and 11b of ceramic material. End plates12 and 13 are provided at the ends of said tube and have shoulderedportions 14 received in the ends of said tube for centering said endplates relative to the tube. These parts are secured together by aspecial process akin to welding. Secured to the end plate 13 is acontactor 15 having a shank 16 extending through said end plate andterminating within tube 11 in a contact 17. The shank 16 extendsoutwardly beyond the plate 13 where it has attached to it a connectornot shown. Opposite the contactor 15 is another contactor 18 which has ashank 21 in alignment with shank 16 and slidably mounted in a guideway22 formed in the end plate 12. To prevent leakage past the guideway 22,a metal bellows 23 is employed which is attached to the end plate 12 andto the shank 21. The shank 21 also has a contact 24 on the inner end ofthe same facing the contact 17. A shield 25 secured to shank 21encircles the bellows 23 while another shield 26 has a flange 25adisposed between the adjoining sections 11a and 11b of the tube 11 andencircles shield 25 and the contacts 17 and 24 and prevents molten metalfrom being deposited on the tube 11.

The support 30 is formed with two side members 31 and 32 connectedtogether at one end by means of an end member 33. The other end of saidsupport has extending across it a flange 34, across the top of it a top35 and at the bottom thereof a bottom 36. Adjacent the flange 34 the top35 is formed with an opening 37. A bracket 38 is bolted to the endmember 33 and rests on and is attached to the insulator 48 by means of abolt 39. The flange 34 on support 30 is bolted to the end plate 12 ofswitch 10 by means of threaded studs 28 issuing from said end plate andnuts 29 screwed thereon. The end plate 13 of switch 30 has bolted to ita bracket 19 similar to the bracket 38 and which is attached to theinsulator 47.

Within the confines of the support 30 is mounted the toggle linkage 50.This linkage consists of two arms 51 and 52 which are pivoted togetherat their adjoining ends by means of a pin 53. The arm 51 has a centralboss 54 journaled on said pin and the arm 52 has two bearings 55 and 56straddling the boss 54 and also mounted on the pin 53. The arm 52further has an elongated boss 57 at its other end which is rotatablymounted on a pin 58. This pin extends through the side members 31 and 32of the support 30 and supports the arm 52 for up and down swingingmovement.

Pivoted to the pin 53 is a link 60 which has spaced bearings 62 and 63which stradle the boss 54. This link travels in a substantially verticaldirection and serves to move the two arms 51 and 52 in a directiontending to bring these arms into or out of alignment.

The arm 51 is formed at its end with a fork 64, which straddles atubular slider 65. A pin 66 secured to the ends of fork 64 extendthrough openings 67 in said slider and supports arm 51 for swingingmovement relative to said slider. The slider 65 is slidably mounted on abolt 71 screwed into the shank 21 of contactor 13 of switch 10.Coaxially disposed relative to the shank 21 is an in terconnecting means80. This means has a sleeve 81 encircling the slider 65 and bolt 71 andformed with a bore 82 of greater diameter than said slider 65 and bolt71 to form an annular space 82 therebetween. A socket 83 in the slider65 communicates with the space 89. At one end of sleeve 81 is an endwall 84 which receives the bolt 71 and which is rigidly clamped againstthe end of shank 21 thereby. At its other end sleeve 81 has formed on itan outwardly extending flange 88. The flange 88 rides in a bore 85formed in the support 30 and the sleeve 81 thereof is spaced from saidbore to provide a space 86 between said bore and sleeve. The bore 85terminates short of the flange 34 of support 30 to form a shoulder 87 atthe end of said bore. Mounted in the space 89 and socket 83 is acompression coil spring 91, which is seated at one end against the endof the slider 65 and at its other end against the inner surface of theend wall 84 of the interconnecting means 80. Also in the space 86 is aspring 92, which is seated at one end against the shoulder 87 and at theother end against the flange 88.

The chamber within the tube 11 being under vacuum, atmospheric pressureon the end of the shank 21 would force the contact 24 into engagementwith the contact 17 and close the switch. However, spring 92, acting onthe interconnecting means 80, moves said means outwardly and opens theswitch, thus maintaining the switch normally open. When pressure isapplied to the slider 65, the same moves along the space 89 and pusheson spring 91. Spring 91 is more rigid than spring 92, and theint-erconnecting means 80 is moved inwardly until the switch closes.After the switch has closed the slider 65 continues its travelcompressing spring 91 and applying a certain pressure on the contacts 17and 24 which is sufficient to prevent arcing and deformation of saidcontacts while the switch is closed. Upon release of pressure on theslider 65, spring 91 forces the slider back against the head of the bolt71 imparting a shock to the shank 21 and thus breaking any minutewelding between the contacts and finally forcing the contacts apart. Atthis position further movement of the slider aided by the spring 92fully opens the switch.

For operating the toggle linkage an electromagnet 70 is employed. Thiselectromagne-t consists of a core 101. The magnet core includes avertical leg 103 and a horizontal leg 104 issuing outwardly therefrom.Extending upwardly from the leg 104 is a central leg 105, which iscylindrical in form. Encircling the leg 105 is a coil 106 which may beof suitable construction. The electromagnet 70 is mounted on the base 41of truck 40, and is secured thereto by means of screws 107, which extendthrough said base and are screwed into the leg 104 of the core 101.

Extending outwardly from the vertical legs 103 of core 101 are twobearings 108, which rotatably support a shaft 111. This shaft hassecured to it by means of a bolt 112 an armature 113, said armaturebeing adapted to occupy the position shown in full lines in FIGURE 1, orto a position in which the same overlies the pole faces 114 and 115 ofthe core 101. The armature 113 has attached to it by the same bolt 112 alever 116. This lever has a boss 117 at its outer end. An insulated link61 is bolted to the link 60 by means of bolts 79. This link has a fork118 at its outer end which straddles the boss 117. A pin 119 passesthrough this fork and through the boss 117 and journals the lever 116for swinging movement relative to the link 61. Upon energization of thecoil 106 of electromagnet 70 armature 113 is drawn downwardly, raisingthe links 61 and 60. This moves the two arms 51 and 52 toward alignment,urging the slider 65 for movement in a direction tending to close theswitch 10. Stops 121 and 122 secured to support 30 and base 41 limitmovement of the toggle linkage 50.

The method of using the invention is obvious. The mechanism beingmounted on a truck can be wheeled into position within the controlstructure with which it is to be used. The current to be conducted isled to the shanks 16 and 2.1 of the switch by means of suitable leads orcables not shown. Any suitable connector may be used for connecting suchleads or cables to the protruding ends of the said shanks. In the caseofthe shank 21, the leads and connector are movable in the opening 37 inthe support 30. The electromagnet 70 is connected in a suitable controlcircuit not shown, energized by the proper source of voltage. When thecoil 106 of said electromagnet is energized, the armature 113 is drawndown to overlie the pole faces 114 and as previously brought out. This,as previously stated, operates the toggle linkage 50 and closes theswitch 10. Upon de-energization of the electromagnet 70 springs 91 and92 return the parts to normal open position.

The advantages of the invention are manifest. Currents of high value maybe handled by breaking the contacts in a vacuum. A minimum amount ofarcing occurs, and minimum deterioration of the contacts results withthe invention disclosed. Suitable spring pressure is applied to thecontacts to provide the desired pressure during flow of current. Uponde-energization of the electromagnet, spring action returns the movablecontactor into normal position. The springs for procuring the desiredresults are located exteriorly of the switch so that the same can bechanged or altered without taking the switch apart.

Changes in the specific form of the invention, as herein described, maybe made within the scope of what is claimed without departing from thespirit of the invention.

Having described the invention, what is claimed as new and desired to beprotected by Letters Patent is:

1. In a switch mechanism having an evacuated housing, a fixed contactortherein extending through said housing, a movable contactor therein andextending through said housing and movable toward and from the fixedcontactor, the atmospheric pressure urging said movable contact towardsaid movable contact, the combination of:

(a) a toggle linkage comprising two normally angularly disposed arms,

(b) pivot means between said arms,

(c) a link pivoted to said pivot means,

(d) actuating means for imparting longitudinal movement to said linkstending to bring said arms into alignment,

(e) pivot means between one of said arms and a part carried by saidhousing and resisting movement of said second named pivot means awayfrom said first named pivot means,

(f) interconnecting means fixed relative to said moveable contactor andconnected to the other arm, said interconnecting being (g) cup shaped inform and having (h) a cylindrical (i) an end wall, and

(j) a flange extending outwardly from the other end of said cylindricalwall,

(k) resilient means acting between said interconnecting means and a partfixed relative to said housing and urging said movable contactor awayfrom said fixed contactor and,

(l) resilient means acting between said movable contactor and saidsecond named arm and applying pressure between said contactors as thearms are moved toward alignment.

2. The combination according to claim 1 in which:

(a) said first named resilient means engages said flange and a shoulderfixed relative to said housing and,

(b) said second resilient means engages the end wall of saidinterconnecting means and a part carried by said second named arm.

3. The combination according to claim 2 in which:

(a) said second named resilient means engages the end wall of saidinter-connecting means and a slider slidable in said connecting meansand pivoted to said second named arm.

4. In combination:

(a) a wheel supported truck having,

(b) a base, and

(c) uprights at the ends of said base,

((1) insulators extending upwardly from and supported on said uprights,

(e) an evacuated elongated housing,

(f) contactors disposed within said housing,

(g) an elongated support attached to and forming a continuation of saidhousing,

(h) means attaching said housing and support to said insulators,

(i) a toggle linkage carried by said support and moving one of saidcontactors relative to another there of,

(j) an electromagnet mounted on said base and hav- (k) a movablearmature and,

(l) a link pivoted to said toggle linkage and operated by said armature.

References Cited UNITED STATES PATENTS Hauser 335173 Lester et al.200114 Miller 200-114 Hollyday 335 26 Peek et a1. 335166 May et a1200153 10 BERNARD A. GILHEANY, Primazy Examiner.

GEORGE HARRIS, JR., Examiner. H. BROOME, Assistant Examiner.

